Monolithic platen

ABSTRACT

In an embodiment, a chemical mechanical planarization (CMP) system includes: a monolithic platen within a platen housing, wherein the monolithic platen is formed of a single piece of material, wherein the monolithic platen includes: a first portion within a first opening, and a second portion within a second opening, wherein the first portion has a different diameter than the second portion; and a polishing fluid delivery module above the monolithic platen, wherein the polishing fluid delivery module is configured to deliver slurry to the monolithic platen during performance of CMP.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/585,735 entitled “MONOLITHIC PLATEN” filed on Nov. 14, 2017, thecontents of which is incorporated by reference herein in its entirety.

BACKGROUND

Integrated circuits are typically comprised of a plurality ofsemiconductor devices formed in or on a substrate. In currentapplications, integrated circuits can consist of literally thousands ormillions of individual semiconductor devices formed in or on thesubstrate. Typically, large numbers of integrated circuits are formed ona single wafer by selectively exposing regions of the wafer so as toallow for deposition of materials or implantation of impurities into asemiconductor wafer to thereby alter the characteristics of the wafer toproduce the desired different semiconductor devices. The semiconductordevices can be formed in the exposed regions of the wafer usingwell-known masking techniques in conjunction with well-known diffusion,implantation or deposition techniques.

Semiconductor device fabrication techniques have been developed whichallow for a higher density of semiconductor devices to be formed in theintegrated circuit. As the scale of integration has increased and as thesize of the individual semiconductor devices has decreased, it hasbecome more important that integrated circuit designers and fabricatorsconsider the structural integrity of the deposited devices and of theintegrated circuit as a whole.

Repeated deposition of materials into the exposed regions of the wafercan result in the integrated circuit having a non-planar upper surface.As the upper surface of the integrated device becomes less planar, theability to form additional semiconductor devices on the integratedcircuit becomes more difficult. Moreover, the existence of protrusionsin the topography of the integrated circuit affects the structuralintegrity of the circuit and can result in failure of the device.Consequently, integrated circuit designers and fabricators haveincreasingly used planarization techniques to planarize the uppersurface of the integrated circuits during fabrication.

One particular planarization technique is known as chemical mechanicalpolishing or planarization (CMP). CMP is a technique whereby the uppersurface of a wafer is globally planarized by simultaneously abrasivelypolishing and etching the upper surface of the wafer. Basically, thewafer is positioned adjacent a pad that is moved with respect to thewafer and the pad, and a slurry which is typically comprised of anetchant liquid. An abrasive encapsulated within a suspension fluid maybe introduced. The pad is then applied to the wafer so that protrusionsin the surface topography of the integrated circuits on the wafer can beremoved by a combination of abrasive polishing and etching to therebyplanarize and polish the upper surface of the wafer.

However, as CMP processes become increasingly commonplace, costeffective off the shelf CMP systems that perform CMP have becomeincreasingly commonplace and include various sensors and apparatusesthat may monitor process parameters and other aspects of the CMPprocess. For example, various off the shelf systems may feature sensorsembedded in a platen assembly (e.g., multi piece platen) used in CMP.However, some of these various sensors may be unnecessary and undulycomplicate the CMP process despite being part of off the shelf CMPsystems. Therefore, there is a need for improved methods and apparatusfor CMP.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isnoted that various features are not necessarily drawn to scale. In fact,the dimensions and geometries of the various features may be arbitrarilyincreased or reduced for clarity of discussion.

FIG. 1 is a perspective view of a polishing station with a monolithicplaten, in accordance with some embodiments.

FIG. 2A is a side view of the monolithic platen of FIG. 1, in accordancewith some embodiments.

FIG. 2B is a side view of a polishing station with a monolithic platenof a platen assembly form factor, in accordance with some embodiments.

FIG. 2C is a side view of a monolithic platen with a platen assemblyform factor for a specific platen housing, in accordance with someembodiments.

FIG. 3 is an illustration of a polishing station with monolithic-platensand, optionally, platen assemblies in a chemical mechanical polishing orplanarization system, in accordance with some embodiments.

FIG. 4 is a flow chart of a chemical mechanical polishing orplanarization process using a monolithic platen, in accordance with someembodiments.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following disclosure describes various exemplary embodiments forimplementing different features of the subject matter. Specific examplesof components and arrangements are described below to simplify thepresent disclosure. These are, of course, merely examples and are notintended to be limiting. For example, it will be understood that when anelement is referred to as being “connected to” or “coupled to” anotherelement, it may be directly connected to or coupled to the otherelement, or one or more intervening elements may be present.

In addition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,”“above,” “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

The present disclosure provides various embodiments of a monolithicplaten for chemical mechanical polishing or planarization (CMP). Amonolithic platen may be a platen formed of a single monolithic piece. Aplaten may be a flat surface on which CMP is performed. The monolithicplaten may be made of a single or a combination (e.g., a mixture) ofmaterials but is formed as one piece. A monolithic platen may becontrasted with a platen assembly, which is a platen of multiple piecesthat is mechanically assembled and is not a single monolithic piece ofmaterial (and thus not formed as one piece). For example, a platenassembly may include an upper platen on top of a lower platen that maybe mechanically adhered (e.g., attached) together.

By being a single monolithic piece of material, the monolithic platenmay be without weak points (e.g., points sealed mechanically with anO-ring or secured with pins or pin holes) from which damaging mediums(e.g., slurry and/or deionized water (DIW)) may seep into the interiorof the monolithic platen and damage the platen over the course of platenuse (e.g., due to wear and tear). For example, a monolithic platen maynot have an interior for which damaging mediums may enter. In contrast,platen assemblies may have such weak points (and/or an interior) fromwhich they receive damage over the course of platen use.

As introduced above, cost effective off the shelf CMP systems thatperform CMP have become increasingly feature rich by including varioussensors and apparatuses that may monitor process parameters and otheraspects of the CMP process. By being off the shelf, such a CMP systemmay be readily commercially available and/or offered with a standard setof various sensors and apparatuses. Examples of such off the shelf CMPsystems may include the Reflexion GT™ system, REFLEXION® LK CMP system,and MIRRA MESA® system sold by Applied Materials, Inc., of Santa Clara,Calif., USA. Examples of such sensors and apparatuses include an endpoint detector that may detect the amount of CMP planarization (e.g.,thinness of the wafer undergoing CMP). An end point detector may includea laser module from which laser reflections off of a wafer may bemonitored to determine the amount of CMP planarization. It has becomeincreasingly common for such sensors and apparatuses to be includedwithin a platen, such as a laser module or an end point detector withinthe platen to monitor a wafer undergoing CMP above the platen. Platensthat include such sensors or apparatuses may be a platen assembly,discussed above, formed of multiple pieces (e.g., upper platen and alower platen) to include the embedded sensor or apparatus. Thesemultiple pieces may be mechanically adhered together in order toencapsulate the embedded sensors or apparatuses in a platen assembly.Also, by having sensors or apparatuses in a platen assembly, the platenassembly may have an opening (e.g., an opening along a top surface of aplaten assembly, or along an upper platen) for which the sensor maymonitor a wafer undergoing CMP.

However, as discussed above, platen assemblies may include weak pointsor interiors that are susceptible to damaging mediums, which may beexacerbated by prolonged use. Furthermore, platen assemblies may beespecially susceptible to damaging mediums relative to monolithicplatens as a platen is typically moved (e.g., rotated) during CMPprocesses, with pressure (e.g., a downward pressure) applied to an uppersurface of the platen. For example, shear pressures may be more presentin platen assemblies (than monolithic platens) due to a pressuredifferential between an upper platen that receives downward pressure anda lower platen that contacts the upper platen while being moved duringCMP processes. Furthermore, platens (e.g., a platen assembly or amonolithic platen) experience relatively more wear and abrasion duringCMP than other components of a CMP system as damaging mediums (e.g.,slurry or deionized water) may be spread along the edges and surfaces ofa platen and travel along the sides (e.g., coating at least a portion ofthe sidewalls) of the platen to drip off of a platen edge (e.g., alongthe side of a platen). Over time, this exposure to such damaging mediumsmay erode a platen, for example by entering the weak points of a platenassembly.

However, such off the shelf CMP systems may be cost effective due tobeing produced at an economy of scale with standard features.Furthermore, the various sensors and apparatuses on conventional CMPsystems (e.g., off the shelf CMP systems) may be utilized in certainapplications. However, there may be applications that do not utilize allof the various sensors and apparatus for such conventional CMP systems,such as the various sensors and apparatuses that may be embedded in aplaten assembly and/or that would require use of a platen assembly.Accordingly, it may be desirable to utilize such off the shelf CMPsystems but to substitute unnecessary or undesirable parts from such offthe shelf CMP systems. For example, a platen assembly may not bedesirable for certain applications and may be substituted with amonolithic platen while preserving the remainder of the off the shelfCMP system, in accordance with various embodiments.

Furthermore, monolithic platens may be designed to facilitateinterchange with platen assemblies. For example, as will be discussedfurther below, monolithic platens may be constructed with a form factorand configured for reception within a platen housing designed for aplaten assembly. In certain embodiments, monolithic platens and platenassemblies may have at least one inside corner along a side of themonolithic platen to facilitate reception within a platen housingdesigned for platen assembly. An inside corner may be a corner formed bytwo intersecting surfaces at an angle measured from the outside (e.g.,external to the monolithic platen or within an opening of the platenhousing) of less than 180 degrees. In certain embodiments, an insidecorner may be at a right angle. In various embodiments, the insidecorner may be a tapered sidewall. In further embodiments, there may bemultipole inside corners, such as two or more inside corners.

Also, CMP systems may be adapted to substitute a platen assembly for amonolithic platen by making according changes to the operation for theCMP system (e.g., by configuring a controller, discussed further below).For example CMP systems may be adapted to substitute a platen assemblyfor a monolithic platen by turning off or ignoring controller operationsfor sensors or apparatuses that would require a platen assembly.

Furthermore, utilization of monolithic platens (e.g., by replacingplaten assemblies with monolithic platens) resolves a long felt butunresolved need in semiconductor processing. Conventional platenassemblies in off the shelf CMP systems have suffered from rapiddegradation. These degraded conventional platen are typically replacedin an off the shelf CMP system at significant expense (e.g., productionand maintenance costs). This may result in undesirable extendeddowntimes for conventional (e.g., off the shelf) CMP systems. However, amonolithic platen may improve the working life of a platen by, forexample, from about 200 hours to about 400 hours per year when comparedto a conventional platen assembly. Thus, semiconductor device productionand maintenance costs can be significantly reduced.

FIG. 1 is a perspective view of a polishing station 100 with amonolithic platen 102, in accordance with some embodiments. Themonolithic platen 102 may be supported and rotated via a rotary rod 104.A platen (whether the monolithic platen 102 or a platen assembly) may berotated during operation (e.g., polishing) using the rotary rod 104. Thepolishing station 100 may be part of an off the shelf CMP system that ismodified to have a platen assembly (e.g., the platen that came with theoriginal off the shelf CMP system formed of multiple pieces) replacedwith the monolithic platen 102 (e.g., a platen formed of one piece thatdoes not come with the original off the shelf CMP system).

The polishing station 100 may also have a polishing fluid deliverymodule (e.g., slurry) 106, pad conditioner module 108, polishing pad110, and a carrier head 112. These parts of the polishing station 100may be original to the off the shelf CMP system and not replaced in themanner that the monolithic platen 102 replaces a platen assembly. Thepolishing pad 110 may have a polishing surface capable of polishing oneor multiple wafers (e.g., substrates) at a same time and a matchingnumber of polishing units for each of the wafers

Each of the polishing units may include one or more carrier heads 112, apad conditioner module 108 and a polishing fluid delivery module 106. Inone embodiment, the polishing fluid delivery module 134 may comprise aslurry delivery arm. The polishing pad 110 may be supported on themonolithic platen 102 which rotates the polishing pad 110 duringprocessing. In one embodiment, the polishing surface of the polishingpad is suitable for CMP (e.g., by performing a chemical mechanicalpolishing and/or an electrochemical mechanical polishing process).

The polishing station 100 is adapted to position the pad conditionermodule 108 and the carrier head 112 in contact with the polishingsurface (e.g., upper surface) of the polishing pad 110, and further isadapted to provide a relative motion therebetween. The carrier head 112may physically move a wafer and transfer a polishing force (e.g.,downward force) to the wafer, sandwiching the wafer between the carrierhead 112 and the polishing pad 110. The pad conditioner module 108 has adistal end coupled to the polishing pad (via the conditioning head 114of the pad conditioner module 108) and a proximal end coupled to a base(not illustrated) that also supports the rotary rod 104. Theconditioning head 114 may be swept across the polishing surface of thepolishing pad 110 to condition the polishing surface.

Damaging mediums, such as a slurry and/or deionized water, may beprovided by the polishing fluid delivery module 106 as a chemical tofacilitate polishing using the above referenced mechanical processes(e.g., mechanical force between the polishing pad 110 and the carrierhead 112) during the CMP process. The slurry may be abrasive andcorrosive and may degrade the materials that it contacts, especiallyafter repeat exposures. The deionized water may be utilized to diluteand/or clean the polishing station 100 (e.g., by transporting usedslurry away from the polishing station 100). A platen assembly may bemore vulnerable to abrasion and corrosion than a monolithic platen dueto the presence of weak points, as discussed above. Accordingly, thepolishing station 100 of the off the shelf CMP system may desirablyexperience prolonged operational life by substituting the monolithicplaten 102 to replace a platen assembly that may come initiallyinstalled in the polishing station 100.

FIG. 2A is a side view 200 of the monolithic platen 102 of FIG. 1, inaccordance with some embodiments. The monolithic platen 102 may bedisposed within a platen housing 203 of the polishing station 100. Theplaten housing 203 may be a space where a platen may rest and beoperated. Specifically, the platen housing 203 may be a space configuredto receive a platen assembly of the off the shelf CMP system, but alsowhere the monolithic platen 102 may rest and be operated as areplacement for the platen assembly. In some embodiments, the monolithicplaten 102 is secured to the rotary rod 104 via a bearing 204. Also, asintroduced above, damaging mediums 205 such as a slurry and/or deionizedwater may be applied to the polishing surface (e.g., upper surface) ofthe polishing pad 110 and/or the upper surface of the monolithic platen102. Furthermore, during CMP or other operations of the monolithicplaten 102, such damaging mediums may flow off of the monolithic platen102 along the sides 206 (e.g., sidewalls) of the monolithic platenand/or along the sides 206 (e.g., sidewalls) and the bottom 208 of themonolithic platen. Typically, weak points of a platen assembly may bedisposed along the sides of the platen assembly (e.g., at the interfacebetween an upper platen and a lower platen). As one example, weak pointsmay be at an inside corner of the platen assembly where an upper platenand a lower platen meet. Also, weak points may be along the uppersurface of the platen assembly (e.g., as holes or openings for sensorsor other apparatuses within a platen assembly). These weak points maydegrade over time (e.g., due to shear stress between the upper and lowerplaten, or decay of the materials at the weak points) such that thedamaging mediums may enter the platen assembly at the weak points andcause internal damage to the platen assembly.

However, such internal damage or exposure of the damaging mediums to theinside of a platen assembly may be avoided by replacing the platenassembly with a monolithic platen. In contrast with a platen assembly, amonolithic platen may not have any, or at least fewer, weak points orinternal surfaces or cavities. This may be due to the monolithic platenbeing formed of a single piece (in contrast to the multiple pieces of aplaten assembly). Stated another way, the monolithic platen is be solidwithin (e.g., without any cavities or openings).

FIG. 2B is a side view of a polishing station 220 with a monolithicplaten 222 of a platen assembly form factor, in accordance with someembodiments. The polishing station 220 may include many of thecomponents the above discussed polishing stations, which will not berepeated here for brevity. This platen assembly form factor monolithicplaten 222 may be designed to have a form factor (e.g., external shapeor contour) that mirrors a platen assembly, but be formed as a singlepiece, rather than multiple pieces. In certain embodiments, a platenassembly form factor may describe a monolithic platen with at least oneinside corner 224 along a side, which may mirror an interface betweensurfaces of different platens of the platen assembly. As discussedabove, an inside corner may be a corner formed by two intersectingsurfaces of the monolithic platen at an angle measured from the outsideof the monolithic platen of less than 180 degrees. For example, theinside corner may be any of 30 degrees, 45 degrees, 60 degrees, 90degrees, 120 degrees, 135 degrees, or 140 degrees. In certainembodiments, the inside corner may be greater than 90 degrees so thatthe inside corner may be more open than closed and easier to clean dueto less accumulation of debris (e.g., dust or residue) within the insidecorner. Furthermore, the inside corner may be tapered such that thecorner forms a curve that relates two surfaces together at less than 180degrees (e.g., where respective tangent lines of the two surfaces areless than 180 degrees apart). Also, the platen assembly form factormonolithic platen 222 may include an upper platen part 222A (e.g., firstportion) and a lower platen part 222B (e.g., second portion), asdelineated with dotted lines. These different parts (e.g., the upperplaten part 222A and the lower platen part 222B) may intersect at theinside corner 224 along the side 225 and experience different shearforces. However, in contrast with a platen assembly that has an upperplaten and a lower platen as different pieces that may be adheredtogether (mechanically assembled or combined), this upper platen part222A and lower platen part 222B may be a contour of the platen assemblyform factor monolithic platen 222 that is formed of a single piece. Incertain embodiments, the thickness of the different platen parts may berelated to each other. For example, a ratio of thickness between theupper platen part 222A and the lower platen part 222B may be 1:1, 1:2,1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10. In certain embodiments, theratio of thickness between the upper platen part 222A and the lowerplaten part 222B may be less than 1:5 (e.g., 1:6 or less) so as toreduce the effect of shear forces at an inside angle from thedifferently sized upper and lower platen parts. Also, the inside corner224 may not necessarily be at a 90 degree angel in certain embodiments.

Stated another way, the platen assembly form factor monolithic platen222 may be formed of a single piece, but may include side contours(e.g., at least one inside corner along the side) similar to or thatmirror a platen assembly. Also, by being formed of a single piece, theplaten assembly form factor monolithic platen 222 may have acontinuously non-concave surface. This may contrast with a platenassembly that is not formed as a single piece. For example, a platenassembly may have a concavity (e.g., a hole) in which a sensor may bedisposed Also, a platen assembly may be non-continuous (e.g., by beingformed of more than one piece, with a critical boundary where thesurface of one piece ends and the surface of another piece begins).

Accordingly, by mirroring the form factor of a platen assembly, a platenassembly form factor monolithic platen 222 may fit into a platen housing226 designed to receive a platen assembly. This platen housing 226 mayhave at least one inside corner along its side opposite the side of amonolithic platen. For example, the platen housing 226 may have twoinside corners 227 along its side opposite to the side 225 of themonolithic platen 222 in order to mate with the at least one insidecorner of the monolithic platen 222.

Also, the platen housing 226 may have a first opening 226A and a secondopening 226B that is continuous with (e.g., is within the bounds of) thefirst opening 226A. The first opening 226A may have a first diameterbetween sidewalls 228A of the first opening 226A that is larger than asecond diameter between sidewalls 228B of the second opening 226B.Stated another way, the second opening 226B is continuous with the firstopening 226A as the second opening 226B is within the first diameter ofthe first opening 226A. The sidewalls 228A and 228B opposite the sides225 of the monolithic platen 222, and transitions between the sidewalls222A and 228B (e.g., inside corners), may be a contour of the platenhousing 226. This contour of the platen housing 226 may form an insidecorner 227. Although two openings are discussed above, a platen housing226 may have any number of openings (e.g., three or more) that mayconform to (e.g., have a mirroring contour with) a side 225 surface of amonolithic platen as desired in accordance with different applicationsin various embodiments.

Furthermore, although the platen assembly form factor monolithic platen222 may have a form factor of a platen assembly, it may not have theweak points of a platen assembly, such as a weak point at an interface(e.g., corresponding to the inside corner 224) between where an upperplaten and a lower platen of a platen assembly would meet (e.g., as aseal or an O-ring between the upper platen and lower platen of a platenassembly). Accordingly, none of the inside corners 224 of the monolithicplaten 222 along a side 225 of the monolithic platen 222 may be at aninterface between different pieces or materials. This may be due to themonolithic platen being formed of a single piece. This may be contrastedwith a platen assembly, where at least one of the inside corners along aside of a platen assembly may be an interface between different piecesor materials (e.g., between an upper platen and a lower platen).

As discussed above, the polishing station 220 may include a platenhousing 226 structured to receive a platen assembly (e.g., by having atleast two openings). Accordingly, a platen assembly form factormonolithic platen 222 may fit into a platen housing more easily ifstructured with a form factor that mirrors a form factor of a platenassembly. Also, the platen assembly form factor monolithic platen 222may have an upper surface 230 that is aligned with (e.g., at a samelevel as) an upper edge 232 of the platen housing.

FIG. 2C is a side view of a monolithic platen 250 with a platen assemblyform factor for a specific platen housing 252, in accordance with someembodiments. As discussed above, a platen assembly (that the monolithicplaten 250 may replace) may possesses a unique form factor in order tofit into the specific platen housing 252 configured to receive theplaten assembly (similar to how a key may fit into a keyhole).Accordingly, monolithic platen 250 have a platen assembly form factorthat mirrors a platen assembly to fit into the specific platen housing252. This minoring may be more desirable the more unique the specificplaten housing 252 is. For example, the specific platen housing 252 mayhave a groove or contour 254 for which the platen assembly form factormonolithic platen 250 may conform to in order to fit inside of thespecific platen housing 252. This contour 254 may include the differentsidewalls 256A and 256B of the specific platen housing 252. As part ofthe specific platen housing 252, the diameter between the firstsidewalls 256A may delineate an upper opening and the diameter betweenthe second sidewalls 256B may delineate a second opening. The upperopening may have a smaller diameter than the lower opening. Also, thiscontour 254 of the platen housing may include at least one inside corner258 opposite the side 260 of the monolithic platen 250. Accordingly, theside 260 of the monolithic platen 250 may also have an inside corner262.

FIG. 3 is an illustration of polishing stations with monolithic platensand, optionally, platen assemblies in a chemical mechanical polishing orplanarization (CMP) system 300, in accordance with some embodiments.This CMP system 300 may utilize monolithic platens 301A exclusively ormay utilize both monolithic platens 301A and platen assemblies 301B.Various aspects of the CMP system will be discussed below.

The CMP system 300 may include a transfer platform 302, a cleaner 304and a polishing station 306. A wet robot module 308 may be provided totransfer wafers (e.g., substrates) 310 between the transfer platform 302and the polishing station 306. The wet robot module 308 may also beconfigured to transfer wafers between the polishing station 306 and thecleaner 304. The transfer platform 302 includes a dry robot 311 which isconfigured to transfer wafers 310 between one or more cassettes 314 andone or more transfer platforms 302. The dry robot 311 is configured toreceive wafers from the cleaner 304 and return the clean polished wafersto the wafers storage cassettes 314. In certain embodiments, referenceto a CMP system may only refer to the polishing station 306 exclusively(e.g., exclusive of the transfer platform 302, cleaner 304, wet robotmodule 308, or cassettes 314).

The polishing station 306 includes a plurality of polishing stations 324with monolithic platens 301A or platen assemblies 301B on which wafersor substrates are polished. The polishing stations 324 are sized tointerface with a carriage (not shown) that is mounted to an overheadtrack. The overhead track allows the carriage to be selectivelypositioned around the polishing station 306.

In certain embodiments, two polishing stations 324 with monolithicplatens 301A are shown located in opposite corners of the polishingstation 306. Optionally, a third polishing station 324 (shown inphantom) may be positioned in a corner of the polishing station 324.This third polishing station 324 (shown in phantom) may include a platenassembly 301B. Additional polishing stations 324 with a monolithicplaten or a platen assembly may be integrated in the polishing station306 in CMP systems having a larger footprint.

To facilitate control of the CMP system 300 and processes performedthereon, a controller 390 comprising a central processing unit (CPU)392, memory 394, and support circuits 396, is connected to the CMPsystem 300. The CPU 392 may be one of any form of computer processorthat can be used in an industrial setting for controlling various drivesand pressures. The memory 394 is connected to the CPU 392. The memory394, or computer-readable medium, may be one or more of readilyavailable memory such as random access memory (RAM), read only memory(ROM), floppy disk, hard disk, or any other form of digital storage,local or remote. The support circuits 396 are connected to the CPU 392for supporting the processor in a conventional manner. These circuitsinclude cache, power supplies, clock circuits, input/output circuitry,subsystems, and the like. Also, the CMP system may include a powersource 398.

As discussed above, the CMP system 300 may be complicated with manycomponents. To avoid redesigning and reconstructing an entire CMP system(and to rely rather on more cost effective off the shelf components), amonolithic platen may be utilized in lieu of a platen assembly whileretaining much of an off the shelf CMP system. Such a CMP system 300 maysolve the problems associated with a platen assembly (e.g., weak pointsand unnecessary sensors and apparatuses internal to a platen assembly,as discussed above) while remaining cost effective and easy to use dueto the integration of off the shelf components.

FIG. 4 is a flow chart of a CMP process 400 with a monolithic platen, inaccordance with some embodiments. The CMP process 400 with a monolithicplaten may be performed by a CMP system 300, as discussed above inconnection with FIG. 3. It is noted that the process 400 is merely anexample, and is not intended to limit the present disclosure.Accordingly, it is understood that additional operations may be providedbefore, during, and after the process 400 of FIG. 4, certain operationsmay be omitted, certain operations may be performed concurrently withother operations, and that some other operations may only be brieflydescribed herein.

The method illustrated in the process 400 may solve the problemsassociated with a platen assembly (e.g., weak points and unnecessarysensors and apparatuses internal to a platen assembly, as discussedabove) while remaining cost effective and easy to use due to theintegration of off the shelf components. At block 402, a platen assemblymay be removed from a platen housing of an off the shelf CMP system. Atblock 404, the platen housing may receive a monolithic platen thatconforms (e.g., fits) within the contours of the platen housing.Accordingly, the monolithic platen may replace the platen assembly inthe platen housing. At block 406, CMP (discussed further above) may beperformed using the monolithic platen.

In an embodiment, a chemical mechanical planarization (CMP) systemincludes: a monolithic platen within a platen housing, wherein themonolithic platen is formed of a single piece of material, wherein themonolithic platen includes: a first portion within a first opening, anda second portion within a second opening, wherein the first portion hasa different diameter than the second portion; and a polishing fluiddelivery module above the monolithic platen, wherein the polishing fluiddelivery module is configured to deliver slurry to the monolithic platenduring performance of CMP.

In another embodiment, a chemical mechanical planarization (CMP) systemincludes: a platen housing including: a first opening including a firstdiameter, and a second opening continuous with the first opening, thesecond opening including a second diameter different than the firstdiameter; a platen within the platen housing, wherein the platen isformed of a single piece with a continuously non-concave surface,wherein the platen includes: a first portion within the first opening,and a second portion within the second opening, wherein the first andsecond portions have different diameters.

In another embodiment, a method for performing chemical mechanicalplanarization (CMP) includes: removing a platen assembly from a platenhousing, wherein the platen housing includes: a first opening includinga first diameter, and a second opening continuous with the firstopening, the second opening including a second diameter different thanthe first diameter, wherein the platen assembly includes an upper platenthat conforms with the first opening and a lower platen that conformswith the second opening; inserting a monolithic platen into the platenhousing, wherein the monolithic platen is formed as one piece, whereinthe monolithic platen comprises: a first portion within the firstopening, and a second portion within the second opening, wherein thefirst and second portions have different diameters.

The foregoing outlines features of several embodiments so that thoseordinary skilled in the art may better understand the aspects of thepresent disclosure. Those skilled in the art should appreciate that theymay readily use the present disclosure as a basis for designing ormodifying other processes and structures for carrying out the samepurposes and/or achieving the same advantages of the embodimentsintroduced herein. Those skilled in the art should also realize thatsuch equivalent constructions do not depart from the spirit and scope ofthe present disclosure, and that they may make various changes,substitutions, and alterations herein without departing from the spiritand scope of the present disclosure.

Conditional language such as, among others, “can,” “could,” “might” or“may,” unless specifically stated otherwise, are otherwise understoodwithin the context as used in general to convey that certain embodimentsinclude, while other embodiments do not include, certain features,elements and/or steps. Thus, such conditional language is not generallyintended to imply that features, elements and/or steps are in any wayrequired for one or more embodiments or that one or more embodimentsnecessarily include logic for deciding, with or without user input orprompting, whether these features, elements and/or steps are included orare to be performed in any particular embodiment.

Additionally, persons of skill in the art would be enabled to configurefunctional entities to perform the operations described herein afterreading the present disclosure. The term “configured” as used hereinwith respect to a specified operation or function refers to a system,device, component, circuit, structure, machine, etc. that is physicallyor virtually constructed, programmed and/or arranged to perform thespecified operation or function.

Disjunctive language such as the phrase “at least one of X, Y, or Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to present that an item, term, etc., may beeither X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z).Thus, such disjunctive language is not generally intended to, and shouldnot, imply that certain embodiments require at least one of X, at leastone of Y, or at least one of Z to each be present.

It should be emphasized that many variations and modifications may bemade to the above-described embodiments, the elements of which are to beunderstood as being among other acceptable examples. All suchmodifications and variations are intended to be included herein withinthe scope of this disclosure and protected by the following claims.

What is claimed is:
 1. A chemical mechanical planarization (CMP) system,comprising: a monolithic platen within a platen housing, wherein themonolithic platen is formed of a single piece of material, wherein themonolithic platen comprises: a first portion within a first opening, anda second portion within a second opening, wherein the first portion hasa different diameter than the second portion; and a polishing fluiddelivery module above the monolithic platen, wherein the polishing fluiddelivery module is configured to deliver slurry to the monolithic platenduring performance of CMP.
 2. The system of claim 1, further comprising:the platen housing comprising: the first opening comprising a firstdiameter, and the second opening continuous with the first opening,wherein the second opening comprises a second diameter different thanthe first diameter.
 3. The system of claim 2, further comprising: apolishing station comprising the platen housing a cleaner; and a factoryinterface.
 4. The system of claim 2, wherein an upper edge of the platenhousing is aligned with an upper surface of the monolithic platen. 5.The system of claim 2, wherein the monolithic platen comprises oneinside corner and the platen housing comprises two inside corners. 6.The system of claim 2, further comprising: another platen housingcomprising: another first opening comprising the first diameter, andanother second opening continuous with the another first opening, theanother second opening comprising the second diameter; a platen assemblywithin the another platen housing, wherein the platen assemblycomprises: an upper platen within the another first opening, and a lowerplaten below the upper platen within the another second opening, whereinthe upper platen and the lower platen have different diameters.
 7. Thesystem of claim 6, further comprising: a polishing station comprisingthe platen housing and the another platen housing; and a robotconfigured to move a wafer to either the platen housing or the anotherplaten housing.
 8. The system of claim 6, further comprising acontroller configured to control a sensor, wherein the sensor isembedded between the upper platen and the lower platen.
 9. The system ofclaim 6, wherein the platen assembly comprises: an opening along a topsurface, the opening exposing a sensor within the platen assembly; acavity between the upper platen and the lower platen; and a seal at aninterface between the upper platen and the lower platen along a side ofthe platen assembly.
 10. A chemical mechanical planarization (CMP)system, comprising: a platen housing comprising: a first openingcomprising a first diameter, and a second opening continuous with thefirst opening, the second opening comprising a second diameter differentthan the first diameter; a platen within the platen housing, wherein theplaten is formed of a single piece with a continuously non-concavesurface, wherein the platen comprises: a first portion within the firstopening, and a second portion within the second opening, wherein thefirst and second portions have different diameters.
 11. The system ofclaim 10, wherein the first diameter is larger than the second diameter.12. The system of claim 10, wherein the platen is free of a laser modulewithin the platen.
 13. The system of claim 10, wherein the first portionand the second portion experience different shear forces during chemicalmechanical planarization.
 14. The system of claim 10, wherein the platenis formed of a single material and is solid within.
 15. A method forperforming chemical mechanical planarization (CMP), comprising: removinga platen assembly from a platen housing, wherein the platen housingcomprises: a first opening comprising a first diameter, and a secondopening continuous with the first opening, the second opening comprisinga second diameter different than the first diameter, wherein the platenassembly comprises an upper platen that conforms with the first openingand a lower platen that conforms with the second opening; inserting amonolithic platen into the platen housing, wherein the monolithic platenis formed as one piece, wherein the monolithic platen comprises: a firstportion within the first opening, and a second portion within the secondopening, wherein the first and second portions have different diameters.16. The method of claim 15, comprising: rotating the monolithic platenwhile performing CMP on the monolithic platen.
 17. The method of claim15, comprising: applying, to the monolithic platen, a slurry that coatsa part of a sidewall of the monolithic platen.
 18. The method of claim15, wherein the monolithic platen is formed of single material.
 19. Themethod of claim 15, further comprising positioning a wafer over themonolithic platen.
 20. The method of claim 15, wherein the monolithicplaten comprises a continuously non-concave surface.